Upstream compatibility ====================== The fedora package uses a FHS compliant directory layout and does NOT place files below /var/milter-greylist. Instead: * the database is located at /var/lib/milter-greylist/db * the sendmail socket is located at /var/run/milter-greylist/milter-greylist.sock * the pidfile is located at /var/run/ This might be incompatible with online documentation that refers to the original paths. Hence, please use the documentation provided by this package where you should find actual paths. Postfix compatibility ===================== You might need to give 0666 permissions to the socket file: | socket "/var/run/milter-greylist/milter-greylist.sock" 0666 Alternatively, use a TCP socket and setup iptables rules to allow only connections from the postfix user.